The dream merchant of Haight Street, he was also one of the stalwarts of the freewheeling counterculture's notion that everybody should help everybody else. Long before the idea of helping or hindering the homeless became part of the political dialogue of San Francisco, Mr. Thelin was a member of the Diggers, a group of people who gave food and clothing to those who had neither.

He contributed to the Oracle, a counterculture newspaper that flourished during the hippie era.

Mr. Thelin was born in Oakland and raised in San Mateo, San Luis Obispo and Yuba City, earning his Eagle Scout badge along the way. He moved to San Francisco in the early 1960s, after a stint with the Army at a post in Taiwan.

Mr. Thelin and his brother, Jay, opened the Psychedelic Shop on Jan. 3, 1966, and soon had a thriving business from flower children who floated in to buy hallucinogenic paraphernalia and then drifted on through the store for a session in its meditation room, with mandalas on the wall and incense in the air.

Less than two years later, in October 1967, the Thelin brothers declared the hippie movement dead and closed the shop's doors. Mr. Thelin also said they were closing the shop because they were less than enthusiastic about becoming full-time businessmen.

"We're getting rid of all these possessions, in the spirit of Thoreau," Mr. Thelin said, referring to the beads, old flowers, copies of the Berkeley Barb and other trappings of the hippie life.

For the past 30 years, Mr. Thelin lived in Forest Knolls in west Marin County and worked as a carpenter, mason and cab driver.

He is survived by his wife, Marsha, of Forest Knolls; a brother, Jay, of Nevada City (Nevada County); two sisters, Sherrill Overholt of El Dorado Hills, and Roxann Thelin of Novato; a daughter, Kira Gapinski of San Anselmo; three sons, Jasper and Ace Thelin of Forest Knolls and Deva Ferar of Mill Valley; and four grandchildren.

A "celebration of his life" is tentatively planned for 2 p.m. April 14, at Roy's Redwoods in the San Geronimo Valley of Marin County, Jasper Thelin said.